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Two Story Air Flow Issues

New member located in Utah. I moved into my home two years ago and have found our 2nd story master bedroom is 5 degrees cooler in the winter and warmer in the summer. We have one unit in the basement that was installed 3 years ago. Tempstar T9MVX Furnace and EDD4X48LA2 AC (4 ton coil, 5 ton blower) The units run great and heat and cool the basement and first floor just fine. The master is 600 SF fed by two registers. The air flow out of these two registers seems much less than others. They run the full length of the room from the trunk. The room is on the north east side of the house with several windows and a walkout door. Also master bath is fed by a single toe kick vent and is cold / hot as well. The house is 3200 SF. (main - 1400 SF 9 vents, 2nd 1050 SF 6 vents, Base 825 SF 5 vents.

I contacted three contractors and received three totally different opinions on what needed to be done. After that I called my inspector because they also pointed out some safety issues in the mech room that he maybe should have caught. He felt a couple of the companies I had called weren't the most reputable and suggested a couple of others to help. So I've ended up meeting with 6 contractors and I'm still very confused as they all have different ideas.

1. Original contractor: 2nd unit in attic. He also recommended getting three other bids (which I liked). This is primarily why I called other contractors. He's mostly a commercial guy and is very poor at calling back. It took me two months to get him out. He never got back to me with a price.

The next two contractors noticed the safety issues.

1. A 16" x 16" hole was cut into the air return duct inside the mechanical room which also contains the water heater. A big code issue. They also cut a similar size hole in the wall to the basement. I've noticed a strong air pull especially when AC is on from main floor down through basement door.

2. The unit has a 20 x 16 filter but the ducting is only about 18 x 13 which some say is not enough air for that unit.

3. There were a couple of other fairly minor concerns on fresh air supply and the way the vent was installed on the furnace.

2nd Contractor: Repair return air grill by connecting a duct to the wall vent. Install a zoning damper and second t stat on 2nd level. Furnace is two stage but would require a new 2 stage condensing unit.

3rd Contractor: Attacked the install and said there were major changes needed on the furnace. Proposed pulling it out and redoing the ducting to provide flow underneath and put the filter on bottom, redo supply issue, and put in a new 5 ton coil (based on SF and 2 floors undersized). Also fix outside vent issue on furnace (slope which I was able to easily fix) and redo the water heater vent. Price was as much as other contractors.

4th: Considered 2nd unit in attic but when I explained the main issue is in the master he recommended a ductless split system. He seemed very competent and thorough. He would also fix the return issue in mech room and increase the size of the filter area by redoing the box ahead of the filter. All his recommendations made sense. My issue with him is the equipment. He quoted Gree (1 1/2 ton EVO Series GWHI8ACD3D....) on the split system and after researching looks low end (comments?). I'm also considering a high efficient fireplace and when I mentioned that on the phone today he said he could do that as well and quoted a price on a Napoleon that seemed real attractive. Looked it up and appears to be their builder grade. When I asked him about the Gree and said I thought it was chinese he said I think it's Korean and it's like a Kia vs a japanese car. Also said his wholesaler carrys parts etc. He said he could put in anything I wanted but the Mitsubishi etc would be several thousand more. I like the guy but beginning to wonder if he's throwing cheap product to make his bid look good. I was ready to go with him but after today wondering...

5th: This ones interesting: He looked around for a few minutes and had a prepared brochure with a system that uses collapsable dampers installed in each duct that run back to a controller in mech room. There are various options of control from: 2 area, 3 area, or total home. The dampers open and closed based on each room (total home) or each floor (3 area). Seemed to make a lot of sense, but why have I not heard about that other places? Didn't get the best vibe from the guy either. But if someone is familiar with this and thinks it will work I may pursue further??

6th: Fix the return air issue in mech room. Add additional return air line off top of return in mech room, run duct through wall into garage and back into main floor to provide more return air from main floor. Also looked at return air ducts at top of stairs (very little air pull). We pulled the grill and he felt the joist areas weren't sealed very well and may be pulling unconditioned air from garage space etc. He recommended getting a contractor to take dry wall down in garage to access that point and seal it up that would improve return air flow from 2nd story. Start with that and go from there. Didn't say anything about the size of the return air at the filter?? Seemed to make sense and a very low cost option but he also didn't seem too firm on prices or follow through.

Had a cousin in the commercial HVAC come by as well to help clear some confusion. He recommended definetly fixing the return air issue, increase the size of the filter box, and consider a mini split for the master.

This is why I'm posting. What a puzzle??? I'm pretty mechanical and work in the industrial steam market so understand something about air flow, etc but these guys are all over the map. They obviously all want north of $6 K to do the work so it's a significant decision. I also didn't explain to the next contractor what I had already learned, wanted to hear their own ideas. Thought I'd see what your thoughts are and maybe you can help me work through some of this to make a wise decision before spending thousands of dollars.

The other thing that has surprised me is that not one of the contractors called back to see what I decided. Most of them spent an hour or so with me which I really appreciate, but you'd think after investing that kind of time you might follow up. I feel bad they've invested that time, but based on all the varied answers I don't know where to turn next.

Holy cow! Unbelievable. Unfortunately, the rule verse the exception. Where do I start? I almost need to come to your house. So much is wrong. Sizing is wrong, ductwork is wrong, the advice (from the "experts") is wrong.......................good luck.......I sense a good screwing is in your future.

Well obviously the return ducting need attention either way you go. If the return into the garage has leakage this should also be resolved regardless. My opinion is that you look further into the zoning system option or go with a Mitsubishi heatpump ductless. The fireplace would make sense if you were looking for heating only but since your looking for cooling that doesn't make sense. If you consider the zoning system and were to zone the (2) runs only you may be looking for detrimental effects to your system as you will be moving nowhere near the airflow you need through the system as a whole.

On zoning: Are you referring to the control damper system as a possible option? The way I'm reading your reply is zoning the 2 runs only would be detrimental but the more sophisticated individual damper system may be effective? If so is anyone familiar with the effectiveness of what I describe?
The fireplace was being considered as a separate option to replace a gas log so we can leave that out to simplify...

The room is on the north east side of the house with several windows and a walkout door.
I think that this contributes to the temp differences in this area.

your quotes are all over the place.

qoute 6 "We pulled the grill and he felt the joist areas weren't sealed very well and may be pulling unconditioned air from garage space etc."
this would be a concern. if you are pulling low temp air into the return..then it will have an effect
on comfort of the house. I'd check into this with whichever bid/company you decide upon.

at 5 tons for 3200 sq ft..I'd think that someone sized the system.
usually on 3200 sq ft you see multiple systems. and 500 sq ft per ton sizing.
could be problems with ducts & returns. did any of them check out ducts for leaks or restrictions?

best of luck

The cure of the part should not be attempted without the cure of the whole. ~Plato

The "2nd" contractor did plug sf / windows etc into a software program. Others seemed to count registers per level and sf. Seems one unit trying to condition 3 levels is a challenge unless perfectly designed? With all walls finished it seems I'm pretty well stuck with the ducts I have unless I want to install a system in the attic (pretty tight space with a vaulted ceiling over master). But I did list the other options suggested and wanting to know if any of those are worth pursuing?
Thanks

1. Original contractor: 2nd unit in attic.
this would be leaving original unit in place for downstairs & basement and adding how big of a second unit?
is it just the master bedroom suite upstairs (600 sq ft)?
closing off at the plenum & supply in these rooms the ducts for the original install?
is there access to all areas from attic?

think about the fact that now you have original unit...plus minimum 1.5 probably 2 ton (cause they are so close in price) for
upstairs. lot of $$ to throw at 5 degree temp difference.

2nd Contractor: Repair return air grill by connecting a duct to the wall vent. Install a zoning damper and second t stat on 2nd level. Furnace is two stage but would require a new 2 stage condensing unit.

would have to see repair of r/a, how to divide ductwork for second zone..plus cost of condenser & hassle of getting
a decent match.
isn't this the contractor that did window sq ft load? what you need is room by room load not whole house load calc.

3rd Contractor: Attacked the install and said there were major changes needed on the furnace. Proposed pulling it out and redoing the ducting to provide flow underneath and put the filter on bottom, redo supply issue, and put in a new 5 ton coil (based on SF and 2 floors undersized). Also fix outside vent issue on furnace (slope which I was able to easily fix) and redo the water heater vent. Price was as much as other contractors.

hate it when they attack install..be professional. how to redo ductwork if it isn't acessable? filter on bottom of unit as opposed to
in the wall..if r/a is sealed..or will be sealed (which it should be sealed either way) is blowing smoke.
new coil..based on sq ft..nuf said.

4th: Considered 2nd unit in attic but when I explained the main issue is in the master he recommended a ductless split system. He seemed very competent and thorough. He would also fix the return issue in mech room and increase the size of the filter area by redoing the box ahead of the filter. All his recommendations made sense. My issue with him is the equipment

ok so here again...1.5 or 2 tons for 600 sq ft. for 5degree temp difference. never heard of the mini split he is recommending. maybe someone
else has?

5th: This ones interesting: He looked around for a few minutes and had a prepared brochure with a system that uses collapsable dampers installed in each duct that run back to a controller in mech room. There are various options of control from: 2 area, 3 area, or total home. The dampers open and closed based on each room (total home) or each floor (3 area). Seemed to make a lot of sense, but why have I not heard about that other places? Didn't get the best vibe from the guy either. But if someone is familiar with this and thinks it will work I may pursue further??

not sure what a collapsable damper is..motorized damper with zond board(controller) maybe same thing?? I like a zoned system (motorized damper
with multiple tstats..not multiple systems)...but installer HAS to be experienced. this may be why no one else suggested it.
there is always a lot of back and forth about multiple systems vs single system with zones on any hvac board. it takes experience to make
it work & not be a total nightmare. so for me the experience of the company would be important.

6th: Fix the return air issue in mech room. Add additional return air line off top of return in mech room, run duct through wall into garage and back into main floor to provide more return air from main floor. Also looked at return air ducts at top of stairs (very little air pull). We pulled the grill and he felt the joist areas weren't sealed very well and may be pulling unconditioned air from garage space etc. He recommended getting a contractor to take dry wall down in garage to access that point and seal it up that would improve return air flow from 2nd story. Start with that and go from there. Didn't say anything about the size of the return air at the filter?? Seemed to make sense and a very low cost option but he also didn't seem too firm on prices or follow through.

I like the way he thinks. for the minimal temp difference it may be simple as sealing system. not just return side but acessable
supply side also. I'm a start with the simple stuff first kinda person. then you don't have a fortune invested if it isn't the cheaper thing
you fixed. the temp difference sounds like leakage or unbalanced air flow to me.

it goes without saying to fix the safety issues in mechanical room.
fireplace in master bath only solves heating not cooling. is gas log fireplace ventless?
I still think orientation, windows and door contribute to temp difference in this area.
what type windows..double paned..what type window frames?
what type doors & windows in door(s)?

system is 3 years old...did it replace same sized unit?
how long have you been in the house?
has there always been a 5 degree comfort issue in master bedroom?
any other comfort issues?
do you have dampers in bath fans in master bathroom? lot of cold/hot
air enters the rooms if the fan isn't dampered.

more folks will be by soon (I hope) to offer their input.
like George2 said...we almost need to be there to evaluate ourselves!

best of luck

The cure of the part should not be attempted without the cure of the whole. ~Plato

1. Original contractor: 2nd unit in attic.
this would be leaving original unit in place for downstairs & basement and adding how big of a second unit? Yes original left in basement add 3 ton air drive 40 - 60 K Heat BTU & 1.5 - 2 Ton cooling.
is it just the master bedroom suite upstairs (600 sq ft)? No there are two other bedrooms and a hall bath 1050 total sf)
closing off at the plenum & supply in these rooms the ducts for the original install?
is there access to all areas from attic? He planned to access the master and the master bath through the attic

think about the fact that now you have original unit...plus minimum 1.5 probably 2 ton (cause they are so close in price) for
upstairs. lot of $$ to throw at 5 degree temp difference. Yes good point -

2nd Contractor: Repair return air grill by connecting a duct to the wall vent. Install a zoning damper and second t stat on 2nd level. Furnace is two stage but would require a new 2 stage condensing unit.

would have to see repair of r/a, how to divide ductwork for second zone..plus cost of condenser & hassle of getting
a decent match.
isn't this the contractor that did window sq ft load? what you need is room by room load not whole house load calc.

3rd Contractor: Attacked the install and said there were major changes needed on the furnace. Proposed pulling it out and redoing the ducting to provide flow underneath and put the filter on bottom, redo supply issue, and put in a new 5 ton coil (based on SF and 2 floors undersized). Also fix outside vent issue on furnace (slope which I was able to easily fix) and redo the water heater vent. Price was as much as other contractors.

hate it when they attack install..be professional. how to redo ductwork if it isn't acessable? filter on bottom of unit as opposed to
in the wall..if r/a is sealed..or will be sealed (which it should be sealed either way) is blowing smoke.
new coil..based on sq ft..nuf said. - Thanks

4th: Considered 2nd unit in attic but when I explained the main issue is in the master he recommended a ductless split system. He seemed very competent and thorough. He would also fix the return issue in mech room and increase the size of the filter area by redoing the box ahead of the filter. All his recommendations made sense. My issue with him is the equipment

ok so here again...1.5 or 2 tons for 600 sq ft. for 5degree temp difference. never heard of the mini split he is recommending. maybe someone
else has?

5th: This ones interesting: He looked around for a few minutes and had a prepared brochure with a system that uses collapsable dampers installed in each duct that run back to a controller in mech room. There are various options of control from: 2 area, 3 area, or total home. The dampers open and closed based on each room (total home) or each floor (3 area). Seemed to make a lot of sense, but why have I not heard about that other places? Didn't get the best vibe from the guy either. But if someone is familiar with this and thinks it will work I may pursue further??

not sure what a collapsable damper is..motorized damper with zond board(controller) maybe same thing?? I like a zoned system (motorized damper
with multiple tstats..not multiple systems)...but installer HAS to be experienced. this may be why no one else suggested it.
there is always a lot of back and forth about multiple systems vs single system with zones on any hvac board. it takes experience to make
it work & not be a total nightmare. so for me the experience of the company would be important. Rules probably don't let me list the co name, but appears this is their main focus. The Dampers are a heavy duty vinyl type material with pneumatic pumps that inflate them. The top of the line option is made by "My Temp"? Once he was done with that he went into humidification, etc which seemed to be a canned sales pitch. Seemed to answer my questions about the dampers very well and he was part of family that started business, but I come from a family business and that's not always good, if you know what I mean. If my detail helps pin this one down any feedback on history of these sytems is appreciated.

6th: Fix the return air issue in mech room. Add additional return air line off top of return in mech room, run duct through wall into garage and back into main floor to provide more return air from main floor. Also looked at return air ducts at top of stairs (very little air pull). We pulled the grill and he felt the joist areas weren't sealed very well and may be pulling unconditioned air from garage space etc. He recommended getting a contractor to take dry wall down in garage to access that point and seal it up that would improve return air flow from 2nd story. Start with that and go from there. Didn't say anything about the size of the return air at the filter?? Seemed to make sense and a very low cost option but he also didn't seem too firm on prices or follow through.

I like the way he thinks. for the minimal temp difference it may be simple as sealing system. not just return side but acessable
supply side also. I'm a start with the simple stuff first kinda person. then you don't have a fortune invested if it isn't the cheaper thing
you fixed. the temp difference sounds like leakage or unbalanced air flow to me.

it goes without saying to fix the safety issues in mechanical room.
fireplace in master bath only solves heating not cooling. is gas log fireplace ventless? I'm thinking of that for our main floor family / great room and realize it's not related directly to my upstairs issue and obviously won't help with cooling. Let's disregard the fireplace for now.
I still think orientation, windows and door contribute to temp difference in this area.
what type windows..double paned..what type window frames? Double pane aluminum (20 year old house)
what type doors & windows in door(s)? same

system is 3 years old...did it replace same sized unit? Not sure we moved in two years ago and unit had been installed a year earlier. I am in contact with the contractor
how long have you been in the house?
has there always been a 5 degree comfort issue in master bedroom? Since I moved in yes
any other comfort issues? No the rest of the house main floor / basement are satisfactory. I'm thinking windows, north face, vaulted ceiling in master etc and fairly large room with just two vents a long ways from the main trunk are the issue. The master bath does back on to an uninsulated attic that is over the garage. When i moved in I discovered they hadn't sealed the area between upstairs and main floor that was exposed into that attic space. I could see canned lights inside the ceiling space. Hope that makes sense. I have sense sealed that and insulated but makes me wonder what other mistakes are behind the walls. I do think that (the un conditioned attic space) does contribute to the challenge along with the windows and doors. With only one toe kick vent at the end of a trunk in the master bath, it makes it tough to keep up.
do you have dampers in bath fans in master bathroom? lot of cold/hot no bath fan in master (maybe that's why they left the space open below for air - Ha Ha)
air enters the rooms if the fan isn't dampered.

more folks will be by soon (I hope) to offer their input.
like George2 said...we almost need to be there to evaluate ourselves!I agree tough to describe everything. I did call back the original contractor next week to review some of the issues again.
Guess non of your folks are located in Utah??

Hope I answered all your questions. Sure appreciate the input and guidance.

Is a duct inspection worth having done? If so what should I require them to do? Assume all is not created equal in that world and could throw a few more hundred down the drain...

just have time for a couple of questions but will try to get back tomorrow.
duct inspection worth having done?
depends on how much you can see.
I test ducts for leakage...but if you can't get there..
how much of your ductwork is visible/acessable?

comfort issues...master bath that backs on to an uninsulated attic over garage.
bingo! think of this...we build exterior walls water & somewhat air tight to outdoor
temps. but in the attic where temps are extreme.. these walls that are living space
on one side & extereme attic temps on the other side. we put a batt in the wall and call it
good.
hey it is insulated ..right?
kind of...but the insulation is exposed to temps colder/hotter than outside.
here is a link that shows what I'm trying to explain. go to page 5 and
apply this picture to the bathroom wall that is shared with attic.http://www.southface.org/default-int...gkeypoints.pdf

this picture shows you how to add insulation to the wall..but most importantly
make is air tight. if you use a extruded polystyrene foil/foam board..you
reflect summer heat OUT of the wall. works for us here in La. summer & winter.

take a look at where the cold/hot air could be entering these upstairs
rooms with the temp difference. it may not be as hvac related as you
think.
but you should still take care of safety issues & seal returns air tight.

best of luck

The cure of the part should not be attempted without the cure of the whole. ~Plato

I test ducts for leakage...but if you can't get there..
how much of your ductwork is visible/acessable? None - It's all sealed in dry wall except the mech room

Appreciate the info on the insulation = I'll try posting a picture or two of what I found when I first moved in. As I said there was an opening between the floors exposed to that attic over garage. It's easy to reopen. Can I / is it to code to have that space filled with a blown in or one of those poly insulations? I think they could get pretty good access to all the space in there and the floor in the bathroom is cold / hot. I did have another layer of batts put in but as you say still probably air leakage around / through it.

Attached are pictures of what I found at the knee wall in uninsulated garage attic space upon moving in. You can see the open space and then I took pictures through that opening of the space between floors. This backs to the master bath and runs under master bath floor. Could I inuslate this entire space to better seal master bath floor above. I have since closed off and insulated with batts.

The third picture does show the duct to the master bath kick plate. This is at the end of the trunk.